Calvin Murphy calls it a law of the NBA. According to the Houston Rocket guard, the law reads: "When in the playoffs, the team with its back to the wall is the team that plays hardest. And the team that wins."

Murphy's NBA Law was on display for 14,326 in the Kemper Arena tonight. Knowing they had to at least split the first two games of the best-of-seven Western Conference final series, the Kansas City Kings simply outworked the Houston Rockets in the second half to earn an 88-79 victory. That sends the series to Houston for game three Friday at 1-1.

"We've had a lot of good wins in the playoffs, but this one was the best," said Kings Coach Cotton Fitzsimmons. "We knew we couldn't lose two at home and have a chance. Tonight, we took some things away from them, executed better at both ends and played smarter. Now, we're tied up and we've got ourselves a series."

The Kings won this game by cutting their turnovers from 25 Tuesday to 14 tonight, and by playing an aggressive defense that contributed to the Rockets' shooting 13 of 44 from the field in the second half. The game was decided during a six-minute stretch of the fourth quarter when the Kings outscored the Rockets 14-2, turning a 72-67 lead into an 86-69 runaway.

Although he received considerable help, the hero tonight was Reggie King. The 6-foot-6 second year forward from Alabama scored 31 points on 13-of-20 shooting from the field and, just to make the night complete, guarded Moses Malone at the defensive end for much of the night. He held the Rocket superstar to 18 points, 11 under Malone's playoff average and his lowest total in 12 playoff games.

"If just missed shots, didn't get good position," Malone said of his five-of-14 shooting. "I had a bad night."

Malone's bad night was precipitated as much by the King defense as his own deficiencies. When Sam Lacey picked up his second foul early in the first quarter, Fitzsimmons switched King onto the 6-l0 Malone and told him to front the Houston center. If the Rockets tried to lob over King, he received lots of help from Lacey and Scott Wedman from behind. And, when he did get the ball, he was triple-teamed almost instantly.

That left it up to the Rocket guards to open things up from outside. They failed miserably. Tom Henderson was four for 10, Murphy five of 11, Mike Dunleavy one for six and Allen Leavell three for seven. Forward Robert Reid, effective from outside in the opener, was two of eight.

Beside curtailing their turnovers, the Kings outworked the taller Rockets on the boards. The rebounding finished even at 39 each, but when the game was on the line, the Kings came up with offensive rebounds.

Four of their 10 offensive rebounds came from John Lambert who, at 6-10, was guarded by little men Dunleavy and Murphy when he came into the game. "I knew with the little guys on me my job was just to post and then go the boards if I didn't take a shot," Lambert said.

Murphy was disgusted by Lambert's 16 points and five rebounds. "We didn't make him pay the price for playing at guard," he said. "If he's going to play back there, we have to work him, use our quickness, make him realize life back there isn't all peaches and cream."

The Rockets didn't do that though. In fact, they did little right tonight. Even as Coach Del Harris screamed, "Inside, inside," they kept firing ineffectively from outside. For 24 minutes that worked: they shot 57 percent to lead 48-47 at the half. But a five-of-22 third quarter and an eight-of-22 fourth meant defeat.

It again proved that Murphy's Law is still a fact of NBA life.

"They had to win," Murphy said. "We wanted to win. We played. They clawed. Clawing always beats playing."